Trend of emergency department presentations for influenza like illness: Differences between pandemic (2009-2010) and post-pandemic (2010-2011) season


The aim of this paper is to analyze differences between incidence, characteristics and out-comes of patients with Influenza Like Illness (ILI) presenting to a teaching public hospital in Central Italy during pandemic influenza season (2009-2010) and during the post-pandemic outbreak (2010-2011). We performed a retrospective descriptive study, and we identified Emergency Department (ED) presentations for ILI, relying on hospital discharge data administrative database. Bivariate analyses for the outcome of hospital admission were performed for both seasons and a multiple logistic regression model has been developed to evaluate which factors were independently associated with hospital admission. Among all the ED presentations (51,757), visits for ILI were respectively 821 (3.1%) during the pandemic season, and 704 (2.8%) during the post-pandemic one. The pandemic cohort differs significantly from the post-pandemic cohort for every characteristic investigated, with the exception of the length of stay in the ED. Overall in 2009-2010 there were more ED presentations compared to the following season, but hospital admission rates were less than in 2010-2011. Further studies are needed to assess if other variables may affect the use of the ED for ILI in order to try to plan staff and hospital organization.

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Tondo, E. , Marigliano, A. , Pellegrini, I. , Stanislao, F. and D’Errico, M. (2012) Trend of emergency department presentations for influenza like illness: Differences between pandemic (2009-2010) and post-pandemic (2010-2011) season. Health, 4, 1256-1262. doi: 10.4236/health.2012.412185.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] World Health Organization (2009) Fact sheet No 211, influenza (seasonal).
[2] Novel Swine-Origin Influenza A (H1N1) Virus Investigation Team (2009) Emergence of a novel swine-origin influenza A (H1N1) virus in humans. The New England Journal of Medicine, 360, 2605-2615. doi:10.1056/NEJMoa0903810
[3] Rodriguez, A., Martin-Loeches, I., Bonastre, J., Olachea, P., Alvarez-Lerma, F., Zaragozae, R., Guerrerof, J., Blancog, J., Gordoh, F., Pozoi, F., Lorentej, J., Carratalák, J., Corderol, M., Rellom, J., Estebani, A., Leónn, C. and Semicyuc-Ciberes-Reipi Working Group. (2011) First influenza season after the 2009 pandemic influenza: Report of the first 300 ICU admissions in Spain. Medicina Intensiva, 35, 208-216. doi:10.1016/j.medin.2011.03.001
[4] Neuzil, K.M., Maynard, C., Griffin, M.R. and Heagerty, P. (2003) Winter respiratory viruses and health care use: A population-based study in the northwest United States. Clinical Infectious Diseases, 37, 201-207. doi:10.1086/375604
[5] Schull, M.J., Mamdani, M.M. and Fang, J. (2004) Community influenza outbreaks and emergency department ambulance diversion. Annals of Emergency Medicine, 44, 61-67. doi:10.1016/j.annemergmed.2003.12.008
[6] McDonnell, W.M., Nelson, D.S. and Schunk, J.E. (2012) Should we fear “flu fear” itself? Effects of H1N1 influenza fear on ED use. American Journal of Emergency Medicine, 30, 275-82. doi:10.1016/j.ajem.2010.11.027
[7] Italian National Institute of Health. InfluNet: Epidemiological surveillance.
[8] Italian Ministry of Health. Surveillance system for influenza like illness emergency departments presentations.
[9] Morbidity and Mortality Weekly Report (2011) Update: Influenza activity, United States, 2010-2011 season, and comparison of the 2011-2012 influenza vaccine, 60, 705-712.
[10] Chuang, J.H., Huang, A.S., Huang, W.T., Liu, M.T., Chou, J.H., Chang, F.Y. and Chiu, W.T. (2012) Nationwide surveillance of influenza during the pandemic (2009-10) and post-pandemic (2010-11) periods in Taiwan. PLoS ONE, 7, Article ID: e36120. doi:10.1371/journal.pone.0036120
[11] Sullivan, S.J., Jacobson, R.M., Dowdle, W.D. and Poland, G. (2010) 2009 H1N1 influenza. Mayo Clinic Proceedings, 85, 64-76. doi:10.4065/mcp.2009.0588
[12] Writing Committee of the WHO Consultation on Clinical Aspects of Pandemic (H1N1) 2009 Influenza (2010) Clinical aspects of pandemic 2009 Influenza A (H1N1) virus infection. The New England Journal of Medicine, 362, 1708-1719.
[13] Boyle, J., Crilly, J., Keijzers, G., Wallis, M., Lind, J., Sparks, R. and Ryan, L. (2012) Impact of influenza across 27 public emergency departments in Australia: A 5-year descriptive study. Emergency Medicine Journal, 29, 725-731. doi:10.1136/emermed-2011-200230
[14] Chiatti, C., Barbadoro, P.,Lamura, G., Di Stanislao, F. And Prospero, E. (2011) Improving the delivery of flu vaccine for the older people in times of economic recession. Human Vaccines, 7, 986-988. doi:10.4161/hv.7.9.16693
[15] Chiatti, C., Di Rosa, M., Barbadoro, P., Lamura, G., Di Stanislao, F. and Prospero, E. (2010) Socioeconomic determinants of influenza vaccination among older adults in Italy. Preventive Medicine, 51, 332-333. doi:10.1016/j.ypmed.2010.06.008
[16] Italian Ministry of Health. Vaccination coverage.
[17] Chiatti, C., Barbadoro, P., Marigliano, A., Ricciardi, A., Di Stanislao, F. and Prospero, E. (2011) Determinants of influenza vaccination among adult and older Italian population with chronic obstructive pulmonary disease. Human Vaccines, 7, 1021-1025. doi:10.4161/hv.7.10.16849
[18] Stahl, J.P., Mailles, A., Dacheux, L. and Morand, P. (2011) Epidemiology of viral encephalitis in. Médecine et Maladies Infectieuses, 41, 453-464. doi:10.1016/j.medmal.2011.05.015
[19] Barbadoro, P., Marigliano, A., Ricciardi, A., D’Errico, M.M. and Prospero, E. (2012) Trend of hospital utilizetion for encephalitis. Epidemiology & Infection, 140, 753-764. doi:10.1017/S0950268811001002

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